Coining apparatus



W. J. 'GILLET COINING4 APPARATUS f July 8, 1969 FUod Dnc, T, 1516@ W/LL/AM l GILLET ATTORNEYS United States Patent O 3,453,859 COINING APPARATUS William J. Gillet, Mentor, Ohio, assignor to Parker- Hanniln Corporation, Cleveland, Ohio, a corporation of Ohio Filed Dec. 1, 1966, Ser. No. 598,289 Int. Cl. BZld 37/00 U.S. Cl. 72-412 8 Claims ABSTRACT F THE DISCLOSURE A coining apparatus including a punch having a forming rib projecting therefrom of a greater height than the linal depth of penetration of the rib into a workpiece, and` a pressure regulated fluid motor for urging the punch into engagement with the workpiece to cause the forming rib to penetrate the workpiece in accordance with the regulated pressure.

The present invention relates generally as indicated to coining `apparatus and more particularly to certain improvements in such apparatus for precisely coining flow slots in the nozzle tips of fuel spray nozzles yand the like.

One form of fuel spray nozzle in widespread use for supplying fuel to the combustion chambers of aircraft jet engines includes a body portion having a tip with fuel slots therein which meter the flow `and provide a desired spray pattern. Since a large number of such nozzles are `generally required to spray fuel into a single combustion chamber from spaced points, it is necessary that the quantity of ow and type of 'spray pattern for each nozzle at any given fuel pressure be substantially identical or otherwise the total fuel flow cannot be accurately controlled.

To achieve uniformity of fuel llow and spray pattern for each nozzle, the depth and shape of the flow slots therein must be substantially identical. Heretofore, it has been the usual practice to mill, grind, or coin the flow slots, using positive abutments or stops for controlling the slot depth. However, `substantial difficulty has been encountered in sufficiently accurately locating such stops from one nozzle tip to the other due to tolerance variations lin the tips to obtain the precise depth of slots required for uniformity of flow and spray pattern.

Accordingly, it is a principal object of this invention to provide a novel coining apparatus and method for accurately controlling the depth of flow slots to be formed thereby in nozzle tips. In general, such coining apparatus consists of a punch having raised coining ribs which are forced against the nozzle tips by a constant iluid pressure source to form the ilow slots therein. There are no mechanical stops whatsoever; the fluid pressure determines the depth of the coined slots, whereby so long as the metal of the tips is substantially uniform, there will be substantially uniform depth penetration of the tips by the coining ribs in accordance `with the iluid pressure to provide uniform flow slots.

Another object is to provide such Ia coining apparatus with a novel aligning sleeve having concentric counterbores for accurately locating the punch with respect to the nozzle tips.

Other objects and advantages of the present invention will become apparent as the following description proceeds.

To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawing setting forth in detail a certain illustrative embodiment of the invention, this being indicative, however, of

3,453,859 Patented July 8, 1969 but one of the various ways in which the principles of the invention may be employed.

In suc-h annexed drawing:

FIG. 1 is an elevation view of a preferred form of coining apparatus in accordance with this invention with portions of the adaptor 4and aligning sleeve for the workpiece and punch broken away to show the manner in which the workpiece and punch are coaxially aligned land coining pressure is exerted on the workpiece;

FIG. 2 is an enlarged fragmentary section of the 4adaptor and aligning `sleeve of FIG. 1 with the punch and nozzle body properly located therein;

FIGS. 3 and 4 are enlarged fragmentary perspective views of the punch and nozzle tip, respectively;

FIG. 5 is an enlarged fragmentary sectional view through the punch and nozzle tip showing the maximum depth of penetration of the coining rib into the tip taken on the plane of the line 5 5, FIG. 2; and

FIG. 6 is an enlarged fragmentary perspective View similar` to FIG. 4 but lshowing another form of nozzle tip which may be coined with the apparatus of the present invention.

Referring now in detail to the drawing and first especinally to FIG. l, there is shown a coining apparatus 1 in accordance with this invention which may comprise a base 2 having two or more guide posts 3 projecting upwardly therefrom for vguiding the movement of a platen 4 toward and away from the base 2. Removably mounted on the upper surface of the base 2 is a punch 5 which may have an enlargement 6 at its lower end adapted to be closely received in a recess 7 in the base 2 `and held in place by a retainer plate 8 attached to the base 2 by suitable fasteners 9.

The shank 12 of the punch 5 extends upwardly through a central `aperture 13 in the retainer plate 8 and has a reduced diameter upper end portion 15 with coining ribs 16 on the uppermost end thereof for forming ow slots 17 in the nozzle tip 18 of a fuel nozzle body 19 in a manner to be explained hereafter.

Although the nozzle body 19 configuration may obviously be varied as desired depending on the manner in which it is to be used, in the form illustrated the nozzle tip 18 is located at one end 20 of the nozzle body 19 with an enlarged cylindrical portion 21 immediately adjacent the nozzle tip 18 followed by a larger diameter threaded portion 22 for threading of a cap or the like (not shown) over the nozzle tip 18. The opposite end 25 the nozzle body 19 is also threaded for attachment to an adaptor, not shown, and there is an outwardly projecting flange 26 on the nozzle body 19 between the threaded portions 22, 25 for limiting the extent to which such cap and Iadaptor may be threaded on the respective portions.

As best seen in FIGS. 4 and 5, the outer end 27 of the nozzle tip 18 has a flat circular portion 28 surrounded by a conical seat portion 29 and there are a pair of flow slots 17 formed in the conical seat portion 29 extending in a direction substantially tangential to the circular portion 28, whereby a swirling motion will be imparted to the fuel passing through the flow slots 17 from a chamber dened between the cap and nozzle tip 18 to which fuel is supplied through a central passage 30 in the nozzle body 19 and radial passages 31 in the nozzle tip 18. The nozzle tip 18 is designed primarily for use in fuel spray nozzles for aircraft jet engines and the like, which requires a large number of such nozzles for spraying fuel into the fuel combustion chamber from spaced points. Accordingly, if the total fuel ilow and s pray pattern into the combustion chamber is to be accurately controlled, the depth and shape of the flow slots 17 for all of the nozzles must be substantially identical.

As previously indicated, it has been common practice to mill, grind, or coin the ow slots, using mechanical abutments or stops for controlling the depth of the slots. However, the results obtained have not been very satisfactory, primarily due to the tolerance variations from one nozzle tip to another.

Variations in the depth of the slots 17 have been overcome with the present invention by eliminating the stops altogether and providing a constant fluid or other pressure -for controlling the depth of penetration of the coining ribs 16 into the nozzle tips 18. Thus, as shown in FIG. 1, the movable platen 4 is actuated by a fluid pressure motor 35 whose piston rod 36 is suitably connected to the upper surface of the platen 4. A constant fluid pressure may be supplied to the iiuid pressure motor 35 by a pump 37 and pressure regulator 38 through a conventional control valve 39. A tank 40 may be provided for supplying the fluid for the pump 37 and receiving the discharge from the lluid pressure motol 35 through the control valve 39.

The pressure which is applied to the platen 4 by the liuid pressure motor 35 is transmitted to the nozzle body 19 by an adaptor 41 having a central recess 42 in its lower end of a larger diameter than the threaded end portion 25 of the nozzle body 19 for ready receipt of such threaded end 25 therein and direct contact of the adaptor 41 with the flange 26 on such nozzle body. The upper end of the adaptor 41 has an enlargement 43 which is received in a recess 44 in the lower face of the platen 4 and retained therein by a retainer plate 45 bolted or otherwise secured to the platen. The nozzle tip 18 is maintained in coaxial alignment with the punch 5 by an aligning sleeve 50 having a pair of coaxial bores 51 and 52 in which are received by a close sliding lit the shank 12 of the punch 5 and the enlarged cylindrical portion 21 of the nozzle body 19, respectively. There is also a counterbore 53 in the sleeve 50 adjacent the end of the bore 52 opposite the bore 51 for ready receipt of the larger diameter threaded portion 22 of the nozzle body 19.

Referring next to FIG. 3, the coining ribs 16 may be spaced apart by a xed distance and oppositely angularly disposed to form similarly disposed tangential flow slots 17 of substantially uniform depth in the conical seat portion 29 of the nozzle tip 1S. Alternatively, there may be four such coining ribs properly oriented for forming four flow slots 30 of gradually decreasing depth in the at end face 32 of the nozzle tip 33 of FIG. 6, or any number of such coining ribs may be provided, depending on the number of liow slots desired. In any event, as clearly shown in FIG. 5, the height of the ribs 16 is greater than the depth of the flow slots 17 to be formed thereby to prevent the flat surfaces on the punch 5 adjacent the coining ribs 16 to act as stops during coining.

Moreover, the outer corners 34 of the coining ribs 16 are preferably sharp, square corners, whereby there is a shearing action as the ribs enter the workpiece thereby precluding outward ilow of the metal at the place of penetration.

In operation, the platen 4 is raised with respect to the base 2 by admitting pressure to the rod end of the iuid pressure motor 35 to provide sufficient clearance between the adaptor 41 and sleeve 50 for placement of the nozzle body 19 therebetween and insertion of the enlarged cylindrical portion 21 into the intermediate bore 52 of the sleeve. A spring 55 disposed between the sleeve 50` and retainer plate 8 maintains the sleeve 50 in engagement with the body flange 26. Thereafter, the control valve 39 is actuated to exhaust the rod end of the motor 35 and supply a constant fluid pressure, for example, 100 p.s.i., to the blind end of such motor which forces the sleeve 50 and nozzle body 19 downwardly against the bias of spring 55 to bring the nozzle tip 18 against the coining ribs 16. Since the coining ribs 16 have a height greater than the desired depth of the flow slots 17 to be formed thereby and there are no stops to limit the downward movement 4 of the platen 4, the depth of the slots 17 will be determined by the amount of pressure applied and the material of the nozzle tips. Accordingly, by selecting a suitable material for the nozzle bodies 19, such as 17-4PH stainless steel of uniform composition and hardness, and applying the same predetermined force against the nozzle bodies during coining, there will be a uniform depth penetration of the coining ribs 16 into the nozzle tips 18 to provide uniform flow slots.

When using l7-4PH stainless for the nozzle bodies, it is desirable to hold the nozzle tips 18 against the punch 5 at the prescribed pressure for about ten seconds to substantially eliminate springback of the metal. With softear metals, such as Stellite AMS 5759, however, there is substantially no plastic return, whereby the punch may be retracted immediately and the slot size will be within one percent.

Upon completion of the coining operation, the platen 4 is retracted and the spring 55 strips the nozzle tip 18 from the coining ribs 16, after which the radial flow passage 31 may be drilled.

Other modes of applying the principles of the invention may be employed, change being made as regards the details described, provided the features stated in any of the following claims or the equivalent of such be employed.

I therefore particularly point out and distinctly claim as my invention:

1. Apparatus for coining slots in one end of a workpiece comprising a base, a platen vertically spaced from said base and mounted for vertical movement toward and away therefrom, a punch secured to said base and extending toward said platen, a sleeve having a first bore in one end which is adapted to be closely slidably received on a portion of said punch and a Second bore in the other end concentric with said rst bore which is adapted to receive in close sliding Contact therewith a portion of a workpiece for axially aligning said workpiece with respect to said punch, means for supplying a substantially uniform pressure to said platen for moving said platen to-ward said punch, and means for transmitting such uniform pressure from said platen to said workpiece to force said workpiece into contact with said punch and thereby cause penetration of said punch into said workpiece in accordance with the pressure applied, said workpiece being a nozzle body having a nozzle tip in which at least one slot is to be formed, and said punch having at least one forming rib on the free end for coining such slot, said rib being of a greater height than the final depth of penetration of said rib into the workpiece to form such slot.

2. The apparatus of claim 1 lwherein plural slots are to be formed in the nozzle tip, and said punch has plural forming ribs on the free end for simultaneously coining such slots, said ribs being of a greater height than the final depth of penetration of said ribs into the workpiece to form such slots.

3. Apparatus for coining a depression in a workpiece comprising a punch having a forming rib projecting from one end, means for aligning a workpiece with respect to said forming rib, means for mounting said punch and workpiece for relative movement to bring said forming rib into and out of engagement with the workpiece, iluid motor means for moving said punch and workpiece relative to each other, and means for regulating the pressure supplied to said fluid motor to cause said forming rib to penetrate the workpiece and form a depression therein, said forming rib having a greater height than the final depth of penetration of said rib into the workpiece, whereby the regulated pressure determines such depth of penetration.

4. The apparatus of claim 3 further comprising an adaptor having a recess for receiving one end of the Workpiece, said means for aligning the workpiece with respect to said forming rib comprising a sleeve having concentric bores closely slidably receiving said punch and the other end of said workpiece for maintaining said punch and workpiece in coaxial alignment with each other, said workpiece having an outwardly projecting flange intermediate its ends, and said recess in said adaptor being of suiicent depth for engagement of the end of said adaptor Awith said flange for transmitting pressure from said adaptor to said workpiece through said iiange.

5. The apparatus of claim 4 further comprising spring means for biasing said sleeve and workpiece away from said punch.

6. Apparatus for coining a depression in one end 0f a worpiece comprising a base, a platen vertically spaced from said base and mounted for vertical movement toward and away therefrom, a punch secured to said base and extending toward said platen, said punch having a forming rib projecting from one end, a sleeve having a :first bore in one end which is adapted to be closely slidably received on said one end of said punch and a second bore in the other end concentric with said lirst bore which is adapted to receive in close sliding contact therewith a portion of a workpiece for axially aligning said workpiece with respect to said punch, iiuid motor means for supplying pressure to said platen for moving said platen toward said punch, means for regulating the pressure applied to said platen by said fluid motor means, and means for transmitting such pressure from said platen to said workpiece to force said workpiece into contact with said forming rib and thereby cause penetration of said forming rib into said workpiece, said forming rib having a greater height than the axial depth of penetration of said forming rib into the workpiece, whereby the regulated pressure determines such depth of penetration.

7. The apparatus of claim 6 wherein said means for transmitting pressure from said platen to said workpiece comprises an adaptor secured to said platen, a recess in said adaptor for receipt of one end of said workpiece, and a shoulder on said workpiece adjacent said one end which is engaged by said adaptor for transmitting pressure from said adaptor to said workpiece through said ange.

8. The apparatus of claim 6 further comprising spring means between said base and sleeve for biasing said sleeve and thus said workpiece away from said punch.

References Cited UNITED STATES PATENTS 1,344,964 6/ 1920 Russell.

2,003,438 6/ 1935 Guignet 72-353 3,135,140 6/1964 Ottestad et al 72--453 3,267,780 8/1966 Roth 83-7 3,312,098 4/ 1967 Henrickson 72-349 RICHARD J. HERBST, Primary Examiner. 

